CAUTION: MAKE SURE EQUIPMENT COOLING SYSTEM IS OPERATING BEFORE
_______ TURN ON OF ELECTRICAL OR ELECTRONIC SYSTEMS OTHERWISE HEAT DAMAGE TO EQUIPMENT COULD RESULT.

 (4)  
Ensure that inertial navigation systems No. 1, 2 and 3 are on and operating in NAV mode with present position inserted. Main power, platform heading and HSI circuit breakers must be closed (Ref 34-41-00).

 (5)  
Place both VOR/ILS-INS switches to VOR/ILS position.

 (6)  
On ALL EXCEPT AT ALL,
 set COMPASS switch to CAPT 1 - F/O 2.
 Set ATT/COMP STAB switch to CAPT 1 - F/O 2 position.

 (7)  
On AT ALL,
 set COMPASS, INS, ATTITUDE and DEV switches to NORM.

 (8)  
Place COMPASS switch on compass controller panel to SLAVED position.

 E. Test MHRS System Operation
 (1)  
Assure that STBY IGN, FLT INST XFMR, and MHRS circuit breakers on main circuit breaker panel (P6) and MHRS circuit breakers on electronic circuit breaker panel (P7) are closed. Check that standby ignition switch on pilots' overhead panel (P5) is set to NORM. Allow MHRS to stabilize for approximately 5 minutes.

 (a)  
Observe that heading warning flags in HSI and RMI are out of view.

 (b)  
Observe that compass cards indicate airplane heading.

 (c)  
Observe that sync annunciator on compass controller is centered.

 (2)  
Place SET HDG knob on compass controller to first clockwise position and hold in place.

 (a)  AF 121, 122, 157, 161, 183, 184;

 EFFECTIVITY
 

 ALL  17 Page 501  Sep 25/9434-21-00
 Observe that compass cards indicate an increase in heading at the rate of 200 to 400 degrees per minute. XA ALL EXCEPT AF 121, 122, 157, 161, 183, 184;
 (b)  observe that compass cards indicate an increase in heading at the rate of 40 to 80 degrees per minute.Observe that compass warning flags appear on the flight instruments.
 (3)  (c) Observe that sync annunciator moves away from centered position.Place SET HDG knob in extreme clockwise position and hold in place. (a) Observe that compass cards increase in heading at the rate of 800 to 1200 degrees per minute. (b) Observe that compass warning flags appear on the flight instruments.
 (4)  (c) Observe that sync annunciator moves away from centered position.Place SET HDG knob to first counterclockwise position and hold in place. (a) Observe that compass cards decrease in heading at a rate of 40 to 80 degrees per minute. (b) Observe that compass warning flags appear on the flight instruments.
 (5)  (c) Observe that sync annunciator moves away from centered position.Place SET HDG knob to extreme counterclockwise position and hold in place. (a) Observe that compass cards decrease in heading at a rate of 800 to 1200 degrees per minute. (b) Observe that compass warning flags appear on the flight instruments.
 (6)  (c) Observe that sync annunciator moves away from centered position.Using SET HDG knob, rotate compass card to indicate a difference from actual airplane heading of greater than 15 degrees. Release SET HDG knob.
 (7)  (a) Observe that sync annunciator is approximately 45 degrees from the null position. (b) Observe that it requires from 2 to 5 minutes for compass card to travel 5 degrees toward airplane magnetic heading.Set mode switch on compass controller to DG position. (a) Observe that compass cards remain stable.
 (8)  Using SET HDG knob, displace compass card 90 degrees from actual airplane magnetic heading. (a) Observe that compass card remains at the set heading (90 degrees difference) when SET HDG knob is released. (b) Observe that compass warning flag appears when SET HDG knob is operated and disappears when the knob is released. (c) Observe that sync annunciator on compass controller remains centered.
 (9)  Set mode switch on compass controller to SLAVED position.

 EFFECTIVITY

 

 ALL  26 Page 502  Sep 25/9434-21-00
 (a)  
Observe that compass warning flag retracts within 15 seconds.

 (b)  
Observe that compass card synchronizes to within 2 degrees of airplane magnetic heading.

 (10) On ALL EXCEPT AT ALL, place ATT/COMP STAB switch to CAPT 3 - F/O 2 (for system 1) or CAPT 1 - F/O 3 (for system 2). On AT ALL, set ATTITUDE switch to CAPT 3 (for system 1) or F/O 3 (for system 2).
 (a)  Observe that compass cards enter fast sync mode and compass warning flags appear until compass cards stabilize near airplane magnetic heading.

 NOTE: If platform headings in the normal and standby sources
____ agree in alignment, the compass cards will not enter the fast sync mode when the compass stabilization transfer switch is changed.
　
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本文鏈接地址：747飛機維護手冊AMM CHAPTER 34 - NAVIGATION 第34章導航1(133)